/*
 * jQuery UI Sortable 1.6
 *
 * Copyright (c) 2008 AUTHORS.txt (http://ui.jquery.com/about)
 * Dual licensed under the MIT (MIT-LICENSE.txt)
 * and GPL (GPL-LICENSE.txt) licenses.
 *
 * http://docs.jquery.com/UI/Sortables
 *
 * Depends:
 *	ui.core.js
 */
(function($) {

    $.widget("ui.sortable", $.extend({}, $.ui.mouse, {
        _init: function() {

            var o = this.options;
            this.containerCache = {};
            this.element.addClass("ui-sortable");

            //Get the items
            this.refresh();

            //Let's determine if the items are floating
            this.floating = this.items.length ? (/left|right/).test(this.items[0].item.css('float')) : false;

            //Let's determine the parent's offset
            this.offset = this.element.offset();

            //Initialize mouse events for interaction
            this._mouseInit();

        },
        destroy: function() {
            this.element
                    .removeClass("ui-sortable ui-sortable-disabled")
                    .removeData("sortable")
                    .unbind(".sortable");
            this._mouseDestroy();

            for (var i = this.items.length - 1; i >= 0; i--)
                this.items[i].item.removeData("sortable-item");
        },
        _mouseCapture: function(event, overrideHandle) {

            if (this.reverting) {
                return false;
            }

            if (this.options.disabled || this.options.type == 'static')
                return false;

            //We have to refresh the items data once first
            this._refreshItems(event);

            //Find out if the clicked node (or one of its parents) is a actual item in this.items
            var currentItem = null, self = this, nodes = $(event.target).parents().each(function() {
                if ($.data(this, 'sortable-item') == self) {
                    currentItem = $(this);
                    return false;
                }
            });
            if ($.data(event.target, 'sortable-item') == self)
                currentItem = $(event.target);

            if (!currentItem)
                return false;
            if (this.options.handle && !overrideHandle) {
                var validHandle = false;

                $(this.options.handle, currentItem).find("*").andSelf().each(function() {
                    if (this == event.target)
                        validHandle = true;
                });
                if (!validHandle)
                    return false;
            }

            this.currentItem = currentItem;
            this._removeCurrentsFromItems();
            return true;

        },
        _mouseStart: function(event, overrideHandle, noActivation) {

            var o = this.options;
            this.currentContainer = this;

            //We only need to call refreshPositions, because the refreshItems call has been moved to mouseCapture
            this.refreshPositions();

            //Create and append the visible helper
            this.helper = this._createHelper(event);

            //Cache the helper size
            this._cacheHelperProportions();

            /*
             * - Position generation -
             * This block generates everything position related - it's the core of draggables.
             */

            //Cache the margins of the original element
            this._cacheMargins();

            //Get the next scrolling parent
            this.scrollParent = this.helper.scrollParent();

            //The element's absolute position on the page minus margins
            this.offset = this.currentItem.offset();

            this.offset = {
                top: this.offset.top - this.margins.top,
                left: this.offset.left - this.margins.left
            };

            // Only after we got the offset, we can change the helper's position to absolute
            // TODO: Still need to figure out a way to make relative sorting possible
            this.helper.css("position", "absolute");
            this.cssPosition = this.helper.css("position");

            $.extend(this.offset, {
                click: {//Where the click happened, relative to the element
                    left: event.pageX - this.offset.left,
                    top: event.pageY - this.offset.top
                },
                parent: this._getParentOffset(),
                relative: this._getRelativeOffset() //This is a relative to absolute position minus the actual position calculation - only used for relative positioned helper
            });

            //Adjust the mouse offset relative to the helper if 'cursorAt' is supplied
            if (o.cursorAt)
                this._adjustOffsetFromHelper(o.cursorAt);

            //Generate the original position
            this.originalPosition = this._generatePosition(event);

            //Cache the former DOM position
            this.domPosition = {prev: this.currentItem.prev()[0], parent: this.currentItem.parent()[0]};

            //If the helper is not the original, hide the original so it's not playing any role during the drag, won't cause anything bad this way
            if (this.helper[0] != this.currentItem[0]) {
                this.currentItem.hide();
            }

            //Create the placeholder
            this._createPlaceholder();

            //Set a containment if given in the options
            if (o.containment)
                this._setContainment();

            //Call plugins and callbacks
            this._propagate("start", event);

            //Recache the helper size
            if (!this._preserveHelperProportions)
                this._cacheHelperProportions();


            //Post 'activate' events to possible containers
            if (!noActivation) {
                for (var i = this.containers.length - 1; i >= 0; i--) {
                    this.containers[i]._propagate("activate", event, this);
                }
            }

            //Prepare possible droppables
            if ($.ui.ddmanager)
                $.ui.ddmanager.current = this;

            if ($.ui.ddmanager && !o.dropBehaviour)
                $.ui.ddmanager.prepareOffsets(this, event);

            this.dragging = true;

            this.helper.addClass('ui-sortable-helper');
            this._mouseDrag(event); //Execute the drag once - this causes the helper not to be visible before getting its correct position
            return true;

        },
        _mouseDrag: function(event) {

            //Compute the helpers position
            this.position = this._generatePosition(event);
            this.positionAbs = this._convertPositionTo("absolute");

            if (!this.lastPositionAbs) {
                this.lastPositionAbs = this.positionAbs;
            }

            //Call the internal plugins
            $.ui.plugin.call(this, "sort", [event, this._ui()]);

            //Regenerate the absolute position used for position checks
            this.positionAbs = this._convertPositionTo("absolute");

            //Set the helper position
            if (!this.options.axis || this.options.axis != "y")
                this.helper[0].style.left = this.position.left + 'px';
            if (!this.options.axis || this.options.axis != "x")
                this.helper[0].style.top = this.position.top + 'px';

            //Rearrange
            for (var i = this.items.length - 1; i >= 0; i--) {

                //Cache variables and intersection, continue if no intersection
                var item = this.items[i], itemElement = item.item[0], intersection = this._intersectsWithPointer(item);
                if (!intersection)
                    continue;

                if (itemElement != this.currentItem[0] //cannot intersect with itself
                        && this.placeholder[intersection == 1 ? "next" : "prev"]()[0] != itemElement //no useless actions that have been done before
                        && !$.ui.contains(this.placeholder[0], itemElement) //no action if the item moved is the parent of the item checked
                        && (this.options.type == 'semi-dynamic' ? !$.ui.contains(this.element[0], itemElement) : true)
                        ) {

                    this.direction = intersection == 1 ? "down" : "up";

                    if (this.options.tolerance == "pointer" || this._intersectsWithSides(item)) {
                        this.options.sortIndicator.call(this, event, item);
                    } else {
                        break;
                    }

                    this._propagate("change", event); //Call plugins and callbacks
                    break;
                }
            }

            //Post events to containers
            this._contactContainers(event);

            //Interconnect with droppables
            if ($.ui.ddmanager)
                $.ui.ddmanager.drag(this, event);

            //Call callbacks
            this._trigger('sort', event, this._ui());

            this.lastPositionAbs = this.positionAbs;
            return false;

        },
        _mouseStop: function(event, noPropagation) {

            if (!event)
                return;

            //If we are using droppables, inform the manager about the drop
            if ($.ui.ddmanager && !this.options.dropBehaviour)
                $.ui.ddmanager.drop(this, event);

            if (this.options.revert) {
                var self = this;
                var cur = self.placeholder.offset();

                self.reverting = true;

                $(this.helper).animate({
                    left: cur.left - this.offset.parent.left - self.margins.left + (this.offsetParent[0] == document.body ? 0 : this.offsetParent[0].scrollLeft),
                    top: cur.top - this.offset.parent.top - self.margins.top + (this.offsetParent[0] == document.body ? 0 : this.offsetParent[0].scrollTop)
                }, parseInt(this.options.revert, 10) || 500, function() {
                    self._clear(event);
                });
            } else {
                this._clear(event, noPropagation);
            }

            return false;

        },
        cancel: function() {

            if (this.dragging) {

                this._mouseUp();

                if (this.options.helper == "original")
                    this.currentItem.css(this._storedCSS).removeClass("ui-sortable-helper");
                else
                    this.currentItem.show();

                //Post deactivating events to containers
                for (var i = this.containers.length - 1; i >= 0; i--) {
                    this.containers[i]._propagate("deactivate", null, this);
                    if (this.containers[i].containerCache.over) {
                        this.containers[i]._propagate("out", null, this);
                        this.containers[i].containerCache.over = 0;
                    }
                }

            }

            //$(this.placeholder[0]).remove(); would have been the jQuery way - unfortunately, it unbinds ALL events from the original node!
            if (this.placeholder[0].parentNode)
                this.placeholder[0].parentNode.removeChild(this.placeholder[0]);
            if (this.options.helper != "original" && this.helper && this.helper[0].parentNode)
                this.helper.remove();

            $.extend(this, {
                helper: null,
                dragging: false,
                reverting: false,
                _noFinalSort: null
            });

            if (this.domPosition.prev) {
                $(this.domPosition.prev).after(this.currentItem);
            } else {
                $(this.domPosition.parent).prepend(this.currentItem);
            }

            return true;

        },
        serialize: function(o) {

            var items = this._getItemsAsjQuery(o && o.connected);
            var str = [];
            o = o || {};

            $(items).each(function() {
                var res = ($(o.item || this).attr(o.attribute || 'id') || '').match(o.expression || (/(.+)[-=_](.+)/));
                if (res)
                    str.push((o.key || res[1] + '[]') + '=' + (o.key && o.expression ? res[1] : res[2]));
            });

            return str.join('&');

        },
        toArray: function(o) {

            var items = this._getItemsAsjQuery(o && o.connected);
            var ret = [];
            o = o || {};

            items.each(function() {
                ret.push($(o.item || this).attr(o.attribute || 'id') || '');
            });
            return ret;

        },
        /* Be careful with the following core functions */
        _intersectsWith: function(item) {

            var x1 = this.positionAbs.left,
                    x2 = x1 + this.helperProportions.width,
                    y1 = this.positionAbs.top,
                    y2 = y1 + this.helperProportions.height;

            var l = item.left,
                    r = l + item.width,
                    t = item.top,
                    b = t + item.height;

            var dyClick = this.offset.click.top,
                    dxClick = this.offset.click.left;

            var isOverElement = (y1 + dyClick) > t && (y1 + dyClick) < b && (x1 + dxClick) > l && (x1 + dxClick) < r;

            if (this.options.tolerance == "pointer"
                    || this.options.forcePointerForContainers
                    || (this.options.tolerance != "pointer" && this.helperProportions[this.floating ? 'width' : 'height'] > item[this.floating ? 'width' : 'height'])
                    ) {
                return isOverElement;
            } else {

                return (l < x1 + (this.helperProportions.width / 2) // Right Half
                        && x2 - (this.helperProportions.width / 2) < r // Left Half
                        && t < y1 + (this.helperProportions.height / 2) // Bottom Half
                        && y2 - (this.helperProportions.height / 2) < b); // Top Half

            }
        },
        _intersectsWithPointer: function(item) {

            var isOverElementHeight = $.ui.isOverAxis(this.positionAbs.top + this.offset.click.top, item.top, item.height),
                    isOverElementWidth = $.ui.isOverAxis(this.positionAbs.left + this.offset.click.left, item.left, item.width),
                    isOverElement = isOverElementHeight && isOverElementWidth,
                    verticalDirection = this._getDragVerticalDirection(),
                    horizontalDirection = this._getDragHorizontalDirection();

            if (!isOverElement)
                return false;

            return this.floating ?
                    (((horizontalDirection && horizontalDirection == "right") || verticalDirection == "down") ? 2 : 1)
                    : (verticalDirection && (verticalDirection == "down" ? 2 : 1));

        },
        _intersectsWithSides: function(item) {

            var isOverBottomHalf = $.ui.isOverAxis(this.positionAbs.top + this.offset.click.top, item.top + (item.height / 2), item.height),
                    isOverRightHalf = $.ui.isOverAxis(this.positionAbs.left + this.offset.click.left, item.left + (item.width / 2), item.width),
                    verticalDirection = this._getDragVerticalDirection(),
                    horizontalDirection = this._getDragHorizontalDirection();

            if (this.floating && horizontalDirection) {
                return ((horizontalDirection == "right" && isOverRightHalf) || (horizontalDirection == "left" && !isOverRightHalf));
            } else {
                return verticalDirection && ((verticalDirection == "down" && isOverBottomHalf) || (verticalDirection == "up" && !isOverBottomHalf));
            }

        },
        _getDragVerticalDirection: function() {
            var delta = this.positionAbs.top - this.lastPositionAbs.top;
            return delta != 0 && (delta > 0 ? "down" : "up");
        },
        _getDragHorizontalDirection: function() {
            var delta = this.positionAbs.left - this.lastPositionAbs.left;
            return delta != 0 && (delta > 0 ? "right" : "left");
        },
        refresh: function(event) {
            this._refreshItems(event);
            this.refreshPositions();
        },
        _getItemsAsjQuery: function(connected) {

            var self = this;
            var items = [];
            var queries = [];

            if (this.options.connectWith && connected) {
                for (var i = this.options.connectWith.length - 1; i >= 0; i--) {
                    var cur = $(this.options.connectWith[i]);
                    for (var j = cur.length - 1; j >= 0; j--) {
                        var inst = $.data(cur[j], 'sortable');
                        if (inst && inst != this && !inst.options.disabled) {
                            queries.push([$.isFunction(inst.options.items) ? inst.options.items.call(inst.element) : $(inst.options.items, inst.element).not(".ui-sortable-helper"), inst]);
                        }
                    }
                    ;
                }
                ;
            }

            queries.push([$.isFunction(this.options.items) ? this.options.items.call(this.element, null, {options: this.options, item: this.currentItem}) : $(this.options.items, this.element).not(".ui-sortable-helper"), this]);

            for (var i = queries.length - 1; i >= 0; i--) {
                queries[i][0].each(function() {
                    items.push(this);
                });
            }
            ;

            return $(items);

        },
        _removeCurrentsFromItems: function() {

            var list = this.currentItem.find(":data(sortable-item)");

            for (var i = 0; i < this.items.length; i++) {

                for (var j = 0; j < list.length; j++) {
                    if (list[j] == this.items[i].item[0])
                        this.items.splice(i, 1);
                }
                ;

            }
            ;

        },
        _refreshItems: function(event) {

            this.items = [];
            this.containers = [this];
            var items = this.items;
            var self = this;
            var queries = [[$.isFunction(this.options.items) ? this.options.items.call(this.element[0], event, {item: this.currentItem}) : $(this.options.items, this.element), this]];

            if (this.options.connectWith) {
                for (var i = this.options.connectWith.length - 1; i >= 0; i--) {
                    var cur = $(this.options.connectWith[i]);
                    for (var j = cur.length - 1; j >= 0; j--) {
                        var inst = $.data(cur[j], 'sortable');
                        if (inst && inst != this && !inst.options.disabled) {
                            queries.push([$.isFunction(inst.options.items) ? inst.options.items.call(inst.element[0], event, {item: this.currentItem}) : $(inst.options.items, inst.element), inst]);
                            this.containers.push(inst);
                        }
                    }
                    ;
                }
                ;
            }

            for (var i = queries.length - 1; i >= 0; i--) {
                var targetData = queries[i][1];
                var _queries = queries[i][0];

                for (var j = 0, queriesLength = _queries.length; j < queriesLength; j++) {
                    var item = $(_queries[j]);

                    item.data('sortable-item', targetData); // Data for target checking (mouse manager)

                    items.push({
                        item: item,
                        instance: targetData,
                        width: 0, height: 0,
                        left: 0, top: 0
                    });
                }
                ;
            }
            ;

        },
        refreshPositions: function(fast) {

            //This has to be redone because due to the item being moved out/into the offsetParent, the offsetParent's position will change
            if (this.offsetParent && this.helper) {
                this.offset.parent = this._getParentOffset();
            }

            for (var i = this.items.length - 1; i >= 0; i--) {
                var item = this.items[i];

                //We ignore calculating positions of all connected containers when we're not over them
                if (item.instance != this.currentContainer && this.currentContainer && item.item[0] != this.currentItem[0])
                    continue;

                var t = this.options.toleranceElement ? $(this.options.toleranceElement, item.item) : item.item;

                if (!fast) {
                    if (this.options.accurateIntersection) {
                        item.width = t.outerWidth();
                        item.height = t.outerHeight();
                    }
                    else {
                        item.width = t[0].offsetWidth;
                        item.height = t[0].offsetHeight;
                    }
                }

                var p = t.offset();
                item.left = p.left;
                item.top = p.top;
            }
            ;

            if (this.options.custom && this.options.custom.refreshContainers) {
                this.options.custom.refreshContainers.call(this);
            } else {
                for (var i = this.containers.length - 1; i >= 0; i--) {
                    var p = this.containers[i].element.offset();
                    this.containers[i].containerCache.left = p.left;
                    this.containers[i].containerCache.top = p.top;
                    this.containers[i].containerCache.width = this.containers[i].element.outerWidth();
                    this.containers[i].containerCache.height = this.containers[i].element.outerHeight();
                }
                ;
            }

        },
        _createPlaceholder: function(that) {

            var self = that || this, o = self.options;

            if (!o.placeholder || o.placeholder.constructor == String) {
                var className = o.placeholder;
                o.placeholder = {
                    element: function() {

                        var el = $(document.createElement(self.currentItem[0].nodeName))
                                .addClass(className || self.currentItem[0].className + " ui-sortable-placeholder")
                                .removeClass('ui-sortable-helper')[0];

                        if (!className) {
                            el.style.visibility = "hidden";
                            document.body.appendChild(el);
                            // Name attributes are removed, otherwice causes elements to be unchecked
                            // Expando attributes also have to be removed because of stupid IE (no condition, doesn't hurt in other browsers)
                            el.innerHTML = self.currentItem[0].innerHTML.replace(/name\=\"[^\"\']+\"/g, '').replace(/jQuery[0-9]+\=\"[^\"\']+\"/g, '');
                            document.body.removeChild(el);
                        }
                        ;

                        return el;
                    },
                    update: function(container, p) {
                        if (className && !o.forcePlaceholderSize)
                            return;
                        if (!p.height()) {
                            p.height(self.currentItem.innerHeight() - parseInt(self.currentItem.css('paddingTop') || 0, 10) - parseInt(self.currentItem.css('paddingBottom') || 0, 10));
                        }
                        ;
                        if (!p.width()) {
                            p.width(self.currentItem.innerWidth() - parseInt(self.currentItem.css('paddingLeft') || 0, 10) - parseInt(self.currentItem.css('paddingRight') || 0, 10));
                        }
                        ;
                    }
                };
            }

            //Create the placeholder
            self.placeholder = $(o.placeholder.element.call(self.element, self.currentItem));

            //Append it after the actual current item
            self.currentItem.after(self.placeholder);

            //Update the size of the placeholder (TODO: Logic to fuzzy, see line 316/317)
            o.placeholder.update(self, self.placeholder);

        },
        _contactContainers: function(event) {
            for (var i = this.containers.length - 1; i >= 0; i--) {

                if (this._intersectsWith(this.containers[i].containerCache)) {
                    if (!this.containers[i].containerCache.over) {

                        if (this.currentContainer != this.containers[i]) {

                            //When entering a new container, we will find the item with the least distance and append our item near it
                            var dist = 10000;
                            var itemWithLeastDistance = null;
                            var base = this.positionAbs[this.containers[i].floating ? 'left' : 'top'];
                            for (var j = this.items.length - 1; j >= 0; j--) {
                                if (!$.ui.contains(this.containers[i].element[0], this.items[j].item[0]))
                                    continue;
                                var cur = this.items[j][this.containers[i].floating ? 'left' : 'top'];
                                if (Math.abs(cur - base) < dist) {
                                    dist = Math.abs(cur - base);
                                    itemWithLeastDistance = this.items[j];
                                }
                            }

                            if (!itemWithLeastDistance && !this.options.dropOnEmpty) //Check if dropOnEmpty is enabled
                                continue;

                            this.currentContainer = this.containers[i];
                            itemWithLeastDistance ? this.options.sortIndicator.call(this, event, itemWithLeastDistance, null, true) : this.options.sortIndicator.call(this, event, null, this.containers[i].element, true);
                            this._propagate("change", event); //Call plugins and callbacks
                            this.containers[i]._propagate("change", event, this); //Call plugins and callbacks

                            //Update the placeholder
                            this.options.placeholder.update(this.currentContainer, this.placeholder);

                        }

                        this.containers[i]._propagate("over", event, this);
                        this.containers[i].containerCache.over = 1;
                    }
                } else {
                    if (this.containers[i].containerCache.over) {
                        this.containers[i]._propagate("out", event, this);
                        this.containers[i].containerCache.over = 0;
                    }
                }

            }
            ;
        },
        _createHelper: function(event) {

            var o = this.options;
            var helper = $.isFunction(o.helper) ? $(o.helper.apply(this.element[0], [event, this.currentItem])) : (o.helper == 'clone' ? this.currentItem.clone() : this.currentItem);

            if (!helper.parents('body').length) //Add the helper to the DOM if that didn't happen already
                $(o.appendTo != 'parent' ? o.appendTo : this.currentItem[0].parentNode)[0].appendChild(helper[0]);

            if (helper[0] == this.currentItem[0])
                this._storedCSS = {width: this.currentItem[0].style.width, height: this.currentItem[0].style.height, position: this.currentItem.css("position"), top: this.currentItem.css("top"), left: this.currentItem.css("left")};

            if (helper[0].style.width == '' || o.forceHelperSize)
                helper.width(this.currentItem.width());
            if (helper[0].style.height == '' || o.forceHelperSize)
                helper.height(this.currentItem.height());

            return helper;

        },
        _adjustOffsetFromHelper: function(obj) {
            if (obj.left != undefined)
                this.offset.click.left = obj.left + this.margins.left;
            if (obj.right != undefined)
                this.offset.click.left = this.helperProportions.width - obj.right + this.margins.left;
            if (obj.top != undefined)
                this.offset.click.top = obj.top + this.margins.top;
            if (obj.bottom != undefined)
                this.offset.click.top = this.helperProportions.height - obj.bottom + this.margins.top;
        },
        _getParentOffset: function() {

            //Get the offsetParent and cache its position
            this.offsetParent = this.helper.offsetParent();
            var po = this.offsetParent.offset();

            if ((this.offsetParent[0] == document.body && $.browser.mozilla)	//Ugly FF3 fix
                    || (this.offsetParent[0].tagName && this.offsetParent[0].tagName.toLowerCase() == 'html' && $.browser.msie)) //Ugly IE fix
                po = {top: 0, left: 0};

            return {
                top: po.top + (parseInt(this.offsetParent.css("borderTopWidth"), 10) || 0),
                left: po.left + (parseInt(this.offsetParent.css("borderLeftWidth"), 10) || 0)
            };

        },
        _getRelativeOffset: function() {

            if (this.cssPosition == "relative") {
                var p = this.currentItem.position();
                return {
                    top: p.top - (parseInt(this.helper.css("top"), 10) || 0) + this.scrollParent.scrollTop(),
                    left: p.left - (parseInt(this.helper.css("left"), 10) || 0) + this.scrollParent.scrollLeft()
                };
            } else {
                return {top: 0, left: 0};
            }

        },
        _cacheMargins: function() {
            this.margins = {
                left: (parseInt(this.currentItem.css("marginLeft"), 10) || 0),
                top: (parseInt(this.currentItem.css("marginTop"), 10) || 0)
            };
        },
        _cacheHelperProportions: function() {
            this.helperProportions = {
                width: this.helper.outerWidth(),
                height: this.helper.outerHeight()
            };
        },
        _setContainment: function() {

            var o = this.options;
            if (o.containment == 'parent')
                o.containment = this.helper[0].parentNode;
            if (o.containment == 'document' || o.containment == 'window')
                this.containment = [
                    0 - this.offset.relative.left - this.offset.parent.left,
                    0 - this.offset.relative.top - this.offset.parent.top,
                    $(o.containment == 'document' ? document : window).width() - this.offset.relative.left - this.offset.parent.left - this.margins.left - (parseInt(this.currentItem.css("marginRight"), 10) || 0),
                    ($(o.containment == 'document' ? document : window).height() || document.body.parentNode.scrollHeight) - this.offset.relative.top - this.offset.parent.top - this.margins.top - (parseInt(this.currentItem.css("marginBottom"), 10) || 0)
                ];

            if (!(/^(document|window|parent)$/).test(o.containment)) {
                var ce = $(o.containment)[0];
                var co = $(o.containment).offset();
                var over = ($(ce).css("overflow") != 'hidden');

                this.containment = [
                    co.left + (parseInt($(ce).css("borderLeftWidth"), 10) || 0) - this.offset.relative.left - this.offset.parent.left - this.margins.left,
                    co.top + (parseInt($(ce).css("borderTopWidth"), 10) || 0) - this.offset.relative.top - this.offset.parent.top - this.margins.top,
                    co.left + (over ? Math.max(ce.scrollWidth, ce.offsetWidth) : ce.offsetWidth) - (parseInt($(ce).css("borderLeftWidth"), 10) || 0) - this.offset.relative.left - this.offset.parent.left - this.margins.left,
                    co.top + (over ? Math.max(ce.scrollHeight, ce.offsetHeight) : ce.offsetHeight) - (parseInt($(ce).css("borderTopWidth"), 10) || 0) - this.offset.relative.top - this.offset.parent.top - this.margins.top
                ];
            }

        },
        _convertPositionTo: function(d, pos) {

            if (!pos)
                pos = this.position;
            var mod = d == "absolute" ? 1 : -1;
            var scroll = this[(this.cssPosition == 'absolute' ? 'offset' : 'scroll') + 'Parent'], scrollIsRootNode = (/(html|body)/i).test(scroll[0].tagName);

            return {
                top: (
                        pos.top																	// the calculated relative position
                        + this.offset.relative.top * mod										// Only for relative positioned nodes: Relative offset from element to offset parent
                        + this.offset.parent.top * mod											// The offsetParent's offset without borders (offset + border)
                        + (this.cssPosition == 'fixed' ? -this.scrollParent.scrollTop() : (scrollIsRootNode ? 0 : scroll.scrollTop())) * mod
                        + this.margins.top * mod												//Add the margin (you don't want the margin counting in intersection methods)
                        ),
                left: (
                        pos.left																// the calculated relative position
                        + this.offset.relative.left * mod										// Only for relative positioned nodes: Relative offset from element to offset parent
                        + this.offset.parent.left * mod											// The offsetParent's offset without borders (offset + border)
                        + (this.cssPosition == 'fixed' ? -this.scrollParent.scrollLeft() : (scrollIsRootNode ? 0 : scroll.scrollLeft())) * mod
                        + this.margins.left * mod												//Add the margin (you don't want the margin counting in intersection methods)
                        )
            };
        },
        _generatePosition: function(event) {

            var o = this.options, scroll = this[(this.cssPosition == 'absolute' ? 'offset' : 'scroll') + 'Parent'], scrollIsRootNode = (/(html|body)/i).test(scroll[0].tagName);

            var position = {
                top: (
                        event.pageY																// The absolute mouse position
                        - this.offset.click.top													// Click offset (relative to the element)
                        - this.offset.relative.top												// Only for relative positioned nodes: Relative offset from element to offset parent
                        - this.offset.parent.top												// The offsetParent's offset without borders (offset + border)
                        + (this.cssPosition == 'fixed' ? -this.scrollParent.scrollTop() : (scrollIsRootNode ? 0 : scroll.scrollTop()))
                        ),
                left: (
                        event.pageX																// The absolute mouse position
                        - this.offset.click.left												// Click offset (relative to the element)
                        - this.offset.relative.left												// Only for relative positioned nodes: Relative offset from element to offset parent
                        - this.offset.parent.left												// The offsetParent's offset without borders (offset + border)
                        + (this.cssPosition == 'fixed' ? -this.scrollParent.scrollLeft() : (scrollIsRootNode ? 0 : scroll.scrollLeft()))
                        )
            };

            if (!this.originalPosition)
                return position;										//If we are not dragging yet, we won't check for options

            /*
             * - Position constraining -
             * Constrain the position to a mix of grid, containment.
             */
            if (this.containment) {
                if (position.left < this.containment[0])
                    position.left = this.containment[0];
                if (position.top < this.containment[1])
                    position.top = this.containment[1];
                if (position.left + this.helperProportions.width > this.containment[2])
                    position.left = this.containment[2] - this.helperProportions.width;
                if (position.top + this.helperProportions.height > this.containment[3])
                    position.top = this.containment[3] - this.helperProportions.height;
            }

            if (o.grid) {
                var top = this.originalPosition.top + Math.round((position.top - this.originalPosition.top) / o.grid[1]) * o.grid[1];
                position.top = this.containment ? (!(top < this.containment[1] || top > this.containment[3]) ? top : (!(top < this.containment[1]) ? top - o.grid[1] : top + o.grid[1])) : top;

                var left = this.originalPosition.left + Math.round((position.left - this.originalPosition.left) / o.grid[0]) * o.grid[0];
                position.left = this.containment ? (!(left < this.containment[0] || left > this.containment[2]) ? left : (!(left < this.containment[0]) ? left - o.grid[0] : left + o.grid[0])) : left;
            }

            return position;
        },
        _rearrange: function(event, i, a, hardRefresh) {

            a ? a[0].appendChild(this.placeholder[0]) : i.item[0].parentNode.insertBefore(this.placeholder[0], (this.direction == 'down' ? i.item[0] : i.item[0].nextSibling));

            //Various things done here to improve the performance:
            // 1. we create a setTimeout, that calls refreshPositions
            // 2. on the instance, we have a counter variable, that get's higher after every append
            // 3. on the local scope, we copy the counter variable, and check in the timeout, if it's still the same
            // 4. this lets only the last addition to the timeout stack through
            this.counter = this.counter ? ++this.counter : 1;
            var self = this, counter = this.counter;

            window.setTimeout(function() {
                if (counter == self.counter)
                    self.refreshPositions(!hardRefresh); //Precompute after each DOM insertion, NOT on mousemove
            }, 0);

        },
        _clear: function(event, noPropagation) {

            this.reverting = false;

            //We first have to update the dom position of the actual currentItem
            if (!this._noFinalSort)
                this.placeholder.before(this.currentItem);
            this._noFinalSort = null;

            if (this.helper[0] == this.currentItem[0]) {
                for (var i in this._storedCSS) {
                    if (this._storedCSS[i] == 'auto' || this._storedCSS[i] == 'static')
                        this._storedCSS[i] = '';
                }
                this.currentItem.css(this._storedCSS).removeClass("ui-sortable-helper");
            } else {
                this.currentItem.show();
            }

            if (this.domPosition.prev != this.currentItem.prev().not(".ui-sortable-helper")[0] || this.domPosition.parent != this.currentItem.parent()[0])
                this._propagate("update", event, null, noPropagation); //Trigger update callback if the DOM position has changed
            if (!$.ui.contains(this.element[0], this.currentItem[0])) { //Node was moved out of the current element
                this._propagate("remove", event, null, noPropagation);
                for (var i = this.containers.length - 1; i >= 0; i--) {
                    if ($.ui.contains(this.containers[i].element[0], this.currentItem[0])) {
                        this.containers[i]._propagate("update", event, this, noPropagation);
                        this.containers[i]._propagate("receive", event, this, noPropagation);
                    }
                }
                ;
            }
            ;

            //Post events to containers
            for (var i = this.containers.length - 1; i >= 0; i--) {
                this.containers[i]._propagate("deactivate", event, this, noPropagation);
                if (this.containers[i].containerCache.over) {
                    this.containers[i]._propagate("out", event, this);
                    this.containers[i].containerCache.over = 0;
                }
            }

            this.dragging = false;
            if (this.cancelHelperRemoval) {
                this._propagate("beforeStop", event, null, noPropagation);
                this._propagate("stop", event, null, noPropagation);
                return false;
            }

            this._propagate("beforeStop", event, null, noPropagation);

            //$(this.placeholder[0]).remove(); would have been the jQuery way - unfortunately, it unbinds ALL events from the original node!
            this.placeholder[0].parentNode.removeChild(this.placeholder[0]);

            if (this.options.helper != "original")
                this.helper.remove();
            this.helper = null;
            this._propagate("stop", event, null, noPropagation);

            return true;

        },
        _propagate: function(n, event, inst, noPropagation) {
            $.ui.plugin.call(this, n, [event, this._ui(inst)]);
            var dontCancel = !noPropagation ? this.element.triggerHandler(n == "sort" ? n : "sort" + n, [event, this._ui(inst)], this.options[n]) : true;
            if (dontCancel === false)
                this.cancel();
        },
        plugins: {},
        _ui: function(inst) {
            var self = inst || this;
            return {
                helper: self.helper,
                placeholder: self.placeholder || $([]),
                position: self.position,
                absolutePosition: self.positionAbs,
                item: self.currentItem,
                sender: inst ? inst.element : null
            };
        }

    }));

    $.extend($.ui.sortable, {
        getter: "serialize toArray",
        version: "1.6",
        defaults: {
            accurateIntersection: true,
            appendTo: "parent",
            cancel: ":input",
            delay: 0,
            distance: 1,
            dropOnEmpty: true,
            forcePlaceholderSize: false,
            forceHelperSize: false,
            helper: "original",
            items: '> *',
            scope: "default",
            scroll: true,
            scrollSensitivity: 20,
            scrollSpeed: 20,
            sortIndicator: $.ui.sortable.prototype._rearrange,
            tolerance: "default",
            zIndex: 1000
        }
    });

    /*
     * Sortable Extensions
     */

    $.ui.plugin.add("sortable", "cursor", {
        start: function(event, ui) {
            var t = $('body'), i = $(this).data('sortable');
            if (t.css("cursor"))
                i.options._cursor = t.css("cursor");
            t.css("cursor", i.options.cursor);
        },
        beforeStop: function(event, ui) {
            var i = $(this).data('sortable');
            if (i.options._cursor)
                $('body').css("cursor", i.options._cursor);
        }
    });

    $.ui.plugin.add("sortable", "opacity", {
        start: function(event, ui) {
            var t = ui.helper, i = $(this).data('sortable');
            if (t.css("opacity"))
                i.options._opacity = t.css("opacity");
            t.css('opacity', i.options.opacity);
        },
        beforeStop: function(event, ui) {
            var i = $(this).data('sortable');
            if (i.options._opacity)
                $(ui.helper).css('opacity', i.options._opacity);
        }
    });

    $.ui.plugin.add("sortable", "scroll", {
        start: function(event, ui) {
            var i = $(this).data("sortable"), o = i.options;
            if (i.scrollParent[0] != document && i.scrollParent[0].tagName != 'HTML')
                i.overflowOffset = i.scrollParent.offset();
        },
        sort: function(event, ui) {

            var i = $(this).data("sortable"), o = i.options, scrolled = false;

            if (i.scrollParent[0] != document && i.scrollParent[0].tagName != 'HTML') {

                if ((i.overflowOffset.top + i.scrollParent[0].offsetHeight) - event.pageY < o.scrollSensitivity)
                    i.scrollParent[0].scrollTop = scrolled = i.scrollParent[0].scrollTop + o.scrollSpeed;
                else if (event.pageY - i.overflowOffset.top < o.scrollSensitivity)
                    i.scrollParent[0].scrollTop = scrolled = i.scrollParent[0].scrollTop - o.scrollSpeed;

                if ((i.overflowOffset.left + i.scrollParent[0].offsetWidth) - event.pageX < o.scrollSensitivity)
                    i.scrollParent[0].scrollLeft = scrolled = i.scrollParent[0].scrollLeft + o.scrollSpeed;
                else if (event.pageX - i.overflowOffset.left < o.scrollSensitivity)
                    i.scrollParent[0].scrollLeft = scrolled = i.scrollParent[0].scrollLeft - o.scrollSpeed;

            } else {

                if (event.pageY - $(document).scrollTop() < o.scrollSensitivity)
                    scrolled = $(document).scrollTop($(document).scrollTop() - o.scrollSpeed);
                else if ($(window).height() - (event.pageY - $(document).scrollTop()) < o.scrollSensitivity)
                    scrolled = $(document).scrollTop($(document).scrollTop() + o.scrollSpeed);

                if (event.pageX - $(document).scrollLeft() < o.scrollSensitivity)
                    scrolled = $(document).scrollLeft($(document).scrollLeft() - o.scrollSpeed);
                else if ($(window).width() - (event.pageX - $(document).scrollLeft()) < o.scrollSensitivity)
                    scrolled = $(document).scrollLeft($(document).scrollLeft() + o.scrollSpeed);

            }

            if (scrolled !== false && $.ui.ddmanager && !o.dropBehaviour)
                $.ui.ddmanager.prepareOffsets(i, event);



            //This is a special case where we need to modify a offset calculated on start, since the following happened:
            // 1. The position of the helper is absolute, so it's position is calculated based on the next positioned parent
            // 2. The actual offset parent is a child of the scroll parent, and the scroll parent isn't the document, which means that
            //    the scroll is included in the initial calculation of the offset of the parent, and never recalculated upon drag
            if (scrolled !== false && i.cssPosition == 'absolute' && i.scrollParent[0] != document && $.ui.contains(i.scrollParent[0], i.offsetParent[0])) {
                i.offset.parent = i._getParentOffset();
            }

            // This is another very weird special case that only happens for relative elements:
            // 1. If the css position is relative
            // 2. and the scroll parent is the document or similar to the offset parent
            // we have to refresh the relative offset during the scroll so there are no jumps
            if (scrolled !== false && i.cssPosition == 'relative' && !(i.scrollParent[0] != document && i.scrollParent[0] != i.offsetParent[0])) {
                i.offset.relative = i._getRelativeOffset();
            }

        }
    });

    $.ui.plugin.add("sortable", "zIndex", {
        start: function(event, ui) {
            var t = ui.helper, i = $(this).data('sortable');
            if (t.css("zIndex"))
                i.options._zIndex = t.css("zIndex");
            t.css('zIndex', i.options.zIndex);
        },
        beforeStop: function(event, ui) {
            var i = $(this).data('sortable');
            if (i.options._zIndex)
                $(ui.helper).css('zIndex', i.options._zIndex == 'auto' ? '' : i.options._zIndex);
        }
    });

})(jQuery);
